ASA's Catamaran Challenge app combines the most innovative thinking in the digital education field, with ASA’s experience in teaching sailing, to create a game that allows players to climb aboard and take control of a cruising catamaran. Operating a twin-engine catamaran under power is very different from operating a single-engine monohull, this app is designed to teach you the nuances and allow you to practice these new skills.
Twinscrew Basics
Cruising catamarans have two engines at the stern, one on the port hull and one on the startboard hull. Each of the engines is controlled by its own throttle. Changing the throttles in various ways relative to each other affects the movement of your boat allowing you to preform different manuevers without using the helm/rudders.
Standing Turn
From standing still, it’s possible to turn a catamaran within its own “footprint” using just the throttles. It requires a delicate balance of the throttles, with one in forward gear, and the other in reverse. It takes practice to do a true standing turn and to also bring the turn to a halt in a particular direction.
Looping Turn
At cruising speeds, the rudders on a catamaran are very effective and steering with the helm is usually preferred. However, it's possible to also steer with the engines by offsetting the two throttles so that the boat performs a looping turn. The radius of the turn can be controlled by varying the RPMs, and the direction, of each throttle.
Slow Maneuvering
As your speed through the water drops, the rudders on your catamaran become less effective. This is when you’ll need to use differential power to assist with turning the boat. Building on the concepts learned in the standing turn and looping turn modules this modules ties it all together requiring you to navigate in some close quarter scenarios using only the throttles.
Motoring Astern
So far all the modules have focused on moving forwards, but the same principles apply in reverse. In this module you'll use your new throttle skills to back the catamaran up to a buoy in the water. Learning this skill in open water will give you the confidence you need so that when you're in a marina you'll know exactly what to do.
Mooring Under Power
Approaching a mooring under power with a catamaran is a little easier than with a monohull - if you've completed all the learning modules in this app then you'll know how to use the twinscrews to make the perfect approach.
Docking Under Power
Docking any boat in a slip requires a bit of finese, even more so when it's a large cruising catamaran. Using all the skills you've learning in the app will prepare you to side-tie, dock forwards, and dock backwards giving you the skills to take on any kind of docking situation.